Class, Object & Anonymous object in Java
What is Class?
Class is Blue print on an Object, It is not possible to create an object without class.
Or
Class is logical entity which plays vital role in creating objects.
Syntax for creating class in Java
class classname
{
//Attributes of class
}
What is Object?
Objects: Objects are real world physical entity
Each Object will have state and behaviour
State: All the data members associated with class are termed as state
Behaviour : All the Member function are considered as behaviour
In Java it is possible to create object in 5 ways
New keyword
Clone method
Class.forNane()
Object input stream (Deseriaisation)
Reflection API
In this blog I will explain steps to create object using new keyword.
Steps to create object:
Define public concrete class
Define all the attribute and behaviour
Follow the syntax to create object
class name obj references = new className();
Example
class Employee
{
public String name;
void info()
{
System.out.print(“hello ”+name+ “welcome to my blog”);
}
public static void main(String[] tags)
{
Employee emp = new Employee();
emp.name =“tom”;
emp.info();
}
}
Flow of execution of the code :
JVM search for main method and start executing it, in main method employee object is created with new keyword hence employee object will get stored in heap area and JVM will allot some address to it. JVM also assign name variable as tom. Post initialisation info() is called info() is get executed printing “Hello tom welcome to my blog”.
Anonymous object
The object without the object reference or object name are termed as anonymous object.
Example demonstrates anonymous object for class Employee:
new Employee() // anonymous object